While this is an amazing feature, I don't think it will work past 6.3...
All Nintendo has to do is to bring the Wii U firmware update method to the 3DS: Force a power cycle before starting the update.
Since it's Nintendo and considering how slow they are gateway users might still be safe for 1-2 firmware update.
If they do that, then the NAND read/write hardware mod will come in handy.